The Physiological Response Mechanisms of Plants to Climate Change - Term Paper Example

HYSIОLОGIСАL RЕSРОNSЕ МЕСHАNISMS ОF РLАNTS By: Name: Tutor: City: Date: ТHЕ РHYSIОLОGIСАL RЕSРОNSЕ МЕСHАNISMS ОF РLАNTS TО СLIMАTЕ СHANGЕ Introduction Plants just like many other organisms have been facing numerous challenges due to the climate change that has been taking place globally. As a result, plants have been adopting various physiological mechanisms in the process of responding to climate change. Besides, the current patterns of climatic changes are becoming the main concerns in various areas of both social activities and also the economic activities which include agriculture and forestry (Akman, 2009). Global, climatic change is always the major problem, that face biodiversity, and ecosystem functions. Global change in climatic conditions has been as a result of the greenhouse effect which is mostly caused by emissions of gasses such carbon dioxide and nitrogen gasses among others. In the past century, impacts of climate change have been obvious over many years, in the natural environment. Therefore, climatic changes usually affect the levels of life for all organisms and population species that exist in the natural environment (Challinor, 2007). However, the important issue to all private sectors and also to the public sector is to develop the necessary strategies, in order to adapt to the climatic changes that may occur in future since it is always a must for the climate change to take place. Physiological response of plants to climate change The climatic changes experienced in different regions globally have been forcing plants to adopt mechanisms of ensuring survival in the adverse climatic conditions brought by the climate change. The understanding of how plants respond to physiological processes brought about by the climate change is quite useful in predicting how the future species of the plants will be distributed and also the population variations; hence the implementation of the necessary conservation strategies can be created (Ainsworth, 2010). When bioclimatic models give an important estimation of the potential effects of climate change on how species are distributed, they try to make an assumption that, both plants and animals exist only in the regions with a similar environment with the one they have currently inhabited. Therefore, the prediction of the future species which will be existing are usually predicted by considering the relationship which exists between the parameters of the environment and the range edges which are current. However, some of the bioclimatic models do not put into consideration the biotic interactions of various species of plants, and they, therefore, end up making an assumption that species do not have sufficient elasticity for adapting to the environments which are beyond the ones they are recently occupying now (Chhetri, 2011). Moreover, a plant can be able to adapt to the changes of the environment by either phenotypically, or through microevolution over life spans. However, the models of bioclimatic may also capture the variations pertaining physiology as a result of adaptation through the micro-evolution. Unfortunately, the bioclimatic models do not allow anybody to make use of the processes that are already captured. The environmental changes can only cause around four outcomes of species, in these outcomes, a specific species of plants may become completely extinct or become extirpated. Other species may move their current distribution range to other various places. Species may also adapt to the environmental changes via a change in the genetic constitution of a population. Also, other species may make use of their own phenotypic elasticity in order to survive in other prevailing conditions of an environment. For the shifting of plants to be successful, a suitable location and new habitats are quite necessary however it is not possible for some species to get suitable habitats in the new environment. The change that has been taking place in the genetic constitution of the plant species and also the phenotypic elasticity are some of the outcomes which prevent the local extinction of the species. Despite the fact that a faster rate of climatic change will deter the evolution of adaptive traits in long-lived species, there was a clear proof that macroevolution is heritable and therefore it usually shifts allele frequencies in a population (Ahuja, et al. 2010). On the other hand, phenotypic elasticity is the only adaptive factor for the long-lived species. Physiological response mechanisms The increased climate changes have been forcing plants to adapt to alternative ways of surviving in the adverse climatic conditions. Many regions are now becoming desert due to the reduction in the rainfall patterns that have led to the development of various physiological mechanisms for adapting to the change brought by climate change. For instance, some plants are developing succulence aiming at ensuring that they have enough water necessary for their survival through developing some storage mechanisms. The water can be stored in stems, fleshy leaves or even in rooms using some special structures that can be crucial in the process of retaining water. This is common especially in plants that are in areas that do experience low rainfalls due to the climate change. Some of the plants that have been adapting to this physiological mechanism in response to the climate change can include euphorbias, aloes, and agaves (Easterling, 2005). Besides, storing water, the succulents have adopted other specializations in ensuring that they survive despite the impacts of climate change. For instance, the succulent plants do absorb large amounts of water within a short duration where they can only absorb water in the soils that are wetter than their interiors hence they have been working towards ensuring that maximize water absorption within the short periods of rains. Besides, the other physiological mechanism that plants have been adopting in the process of responding to the climate change can include developing shallow roots. The plants that are in the regions that are facing a reduction in rainfalls due to the climate changes are slowly developing swallow and extensive root systems (Duran, et al. 2010). These root systems are adopted to ensure that water absorption by the roots s maximized as the regions do receive rains within the very short duration. After fast absorption of water by the extensive roots systems, the water is stored to be used during the dry season when the soils are dry. Also, the shallow roots systems are said to come back to life fast when the rains are near as they are in a position to detect the signs of rains hence preparing to harvest water the moment the rains starts. The water harvesting process is done rapidly before the rains come to an end where the roots are almost to the surface to ensure that they harvest water as fast as they can. The roots do ensure that they spread to cover large surface area aiming at increasing their contact with water hence facilitating fast water absorption. The plants protect their stored water by being thorny and bitter making it hard for the animals to interfere with the stored water for the plant. Besides, most of the succulent plants are not easily accessible by animals as they are located in vertical cliffs or canopies of thorny bushes. In the process of reducing water loss due to the high temperature and low rains, plants are now responding by reducing the number of leaves to reduce water loss through transpiration. At some extreme cases, plants in the dry areas are now shading all leaves to ensure minimization of the water loss through leaves. Also, some plants are developing thorns that do replace the functioning of leaves especially the plants in the desert regions. In the dry region, shading leaves and developing thorns has been a common physiological mechanism among plants that has been useful in the process of ensuring that water loss is minimized to the lowest levels possible. Another physiological response mechanism that has been used by the plant in the process of responding to climate change can include waxy cuticles. Plants in the areas that are experiencing a decline in rains due to the effects of climate changes are now developing waxy cuticle that acts as an insulator on the leaves. The insulation role of the cuticle layer of the leaves has been geared towards ensuring that water loss through leave is minimized (Egan, et al. 2012). Besides, considering the high temperatures that have been experienced due to the changes in climate, thick cuticle layer can reduce water loss through evaporation due to high temperatures. Hibernation has been another common physiological mechanism that has been used by plants in the process of responding to climate change. This mechanism has been common during the dry times where the plants are involved in the recycling of carbon dioxide and oxide aiming at reducing levels of photosynthesis. During the hibernation period, the plants are usually dormant where they resume growth after rains. Some of the plants also dry out appearing to be dead aiming at reducing metabolism ready to resume their growth when the rains arrive. Also, some plants have developed some physiological mechanism that has ensured that they evade drought by dying during the dry period. Such plants rely on the seeds hat germinate the moment rains arrives hence the germinating seeds do preserve the species. Seeds have no metabolism and are resistant to drought making such plants species continue existing despite the changing climate. Precipitation changes in plants The increased temperatures due to the global warming are leading to increased evaporation rates in the plants. However, the rate of evaporation is not uniform in the plants as different regions are affected differently by climate change. Increased temperatures in most of the regions are forcing the plants to dry due to losing of water during the dry season. As a result, the plants r developing some physiological changes that are geared towards reducing the loss of water through evaporation during the high temperatures (Argyris, et al. 2008). The climate in different regions has been changing leading to the development of adaptations to survive the high temperatures. For instance, the size of the stomata on the leaves of the plants that are in regions that are facing increased temperatures is becoming small with time. Besides, the number of the stomata is reducing aiming at ensuring that the water loss is minimized. Some other plants are also adopting by changing the times of opening and closing stomata where the plants are now closing their stomata during the day when the temperatures are high and opening during the night when temperatures are low. This is an adaptation of the plants to the change in the climate where plants are responding to adapt to the changes in climate. Also, climate change is leading to temperature changes in some regions where during the day temperatures are high while during the night the temperatures are low (Asada, 2006). The increasing temperatures are affecting the plants differently depending on the amount of rainfall received in the regions. In areas that are dry, increase in temperatures is making the plants in such regions shade leaves to eliminate water loss through leaves. Photosynthesis change in plants The increased temperatures due to global change in climate are affecting plant photosynthesis forcing the plants to develop some physiological mechanisms for responding to the change. The changes that are taking place in the rate of photosynthesis where the photosynthetic enzymes are affected by the resulting high temperatures. The temperatures are affecting the modulation of the photosynthesis rate functioning of the photosynthetic enzymes altered. In the process of responding to the changes in the photosynthesis rate due to the high temperatures, the plants in the high-temperature regions are responding by changing the color of the leaves from green to yellow (Allakhverdiev, et al. 2008). Besides, the plants are ensuring that the rate of photosynthesis is maintained by producing many mesophyll cell, and chloroplast. Climate change is also affecting the concentration of carbon dioxide which is necessary for the photosynthesis process. The changes in the levels of carbon dioxide can be associated with the increased pollution of the environment that has greatly been contributing to the climate change. The increase of carbon dioxide can affect the opening of stomata that do affect the amount of carbon dioxide entering the plant for photosynthesis. This can result in reducing the respiration rate where the plant can experience efficiency in the use of the available water the plants (Bajguz, 2009). The efficiency in the water use can be a response for the plants in the regions that are dry as efficient use of water can result in support of the photosynthesis process as water is needed in the photosynthesis process. The capacity photosynthesis is said to be reduced by the temperature threshold where the chlorophyll fluorescent techniques and carbon dioxide exchange is said to change. There has been a close agreement that has been found between the temperatures exposed to the leaves with the photosynthesis capacity. The capability of the leaves to fix carbon dioxide is said to be low at high temperatures due to the changes that take place in the fluorescence of the chlorophyll (Banti et al. 2010). The decline in the carbon dioxide fixation in the plants cannot be attributed to the stomata response but can be largely associated with the damage caused by the high temperatures on some important components of the plants necessary to the process of photosynthesis. Feedbacks between thermal stress and behavior In the case of climatic change, the both marine and terrestrial plants, have the priority keeping themselves cool. Provided that the behavior of the plants do not require any necessities like water or energy, the exploitation of complex micro-climate mosaics will definitely enable these organisms to encounter the effects of climate change. For example, a plant known as the intertidal sea stars can behaviorally control their thermal temperature by just increasing up the water uptake when it is hot. This response of intertidal sea stars can help them to respond to adverse thermal temperatures. The endothermic organisms such as plants that have complicated thermoregulatory behaviors, these organisms are able to occupy a basic niche with wider environmental variables than those of ectotherms (Barnabás, et al. 2008). However, the endotherms are usually affected by the changes in temperature in their environment; therefore their both activities and the survival of these organisms, are influenced by the type of the temperature change in which they are subjected to. According to the relationship existing between the behavior of plants and environmental temperatures, the temperatures do affect the behavior of the plants. As a result, the plants do develop some mechanism geared towards ensuring survival despite the adverse climatic changes. Some plants have the ability of projecting climatic changes hence starting to respond accordingly at the right time. The change in the climate has been affecting plants different depending on the intensity of the change concerning levels of rain and temperature. The most affected sector by the global warming is the agriculture. For instance, agriculture can be affected by the following factors which are brought about by the global warming. These factors include; atmospheric temperature, humidity, and the soil moisture. While responding to the climatic changes, it is also very important to take care of both markets and also non-markets from any damage that may result from the process of practicing adaptations. The adaptive responses which are practiced in agriculture in order to adapt to the global climate changes include; developing irrigation methods and also improving the crop varieties (Battisti, 2009). The inter-governmental panel gave a report on climate change, concerning the climate change shows that the carbon dioxide gas produced from agriculture, mostly comes from the decomposition of organic matter and plant remains. Methane gas is released when the fermentation of organic materials is taking place. There are ecological effects that have resulted from niche-level heterogeneity, and these consequences have been illustrated in a model system which involves a marine predator and its prey. The body temperature of the prey was marked to be much hotter, as compared to the predator. Therefore, when the thermal temperature rose up, the rate at which the predator consumed the prey also increased, on the other hand, as the thermal temperature went down, the rate at which the predators fed on the prey also decreased. Therefore, the outcome of an ecosystem usually depends on the interaction between the individual thermoregulation of species at various levels and the stresses from the environment. The main aim of these studies is to analyze the stresses of both abiotic and biotic and how this stresses usually influence the distribution of species of organism (Bray, 2000). However, being conversant with both the biophysical modeling and ecological manipulation becomes a strong tool for predicting the effects of climatic change in future. Conclusion Climate change has led to the development of adaptive behavior of the plants to the changes in climate. For instance, various studies have currently explored about the physiological elasticity of both terrestrial and also marine plants. The main thematic issue that has been explored in the studies is that biophysical models that deal with the heat exchange are very significant since they are used in predicting about the environmental space which is occupied by a certain plant species, concerning the thermal stress. More specific, the main purpose of the biophysical modeling is to determine the factors which facilitate the exchange process of heat that do exist between organisms and their surroundings in which they are living in, instead of focusing on the existing relationship between the components of surroundings such as air temperature, and with the body temperature. Therefore, the biophysical models usually grant permission of exploring how changing climatic conditions possibly have impacts on the patterns of distribution of organism species. For the purpose of conserving, these differences which occur between the predictions at the level of population, and also the mismatches which are driven by adverse weather, and climate data are very crucial since the areas noted by the physiological model could work as the refuge for some various species in an environment changed future. The thermal well-being of an organism is always influenced by the micro-climate rather than the macro-climate. A study needs to be conducted concerning the strategies that can be employed to control the increased climate change. References Ahuja I., de Vos R. C. H., Bones A. M., Hall R. D. (2010) Plant molecular stress responses face climate change. Trends Plant Sci. 15 664–674. Ainsworth E. A., Ort D. R. (2010) How do we improve crop production in a warming world? Plant Physiol. 154 526–530. Akman Z. (2009) Comparison of high temperature tolerance in maize, rice and sorghum seeds by plant growth regulators. J. Anim. Vet. 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